Characterization of Recombination Properties and Contact Resistivity of Laser-Processed Localized Contacts From Doped Silicon Nanoparticle Ink and Spin-On Dopants

An increase in market share of very high-efficiency solar cell concepts, such as interdigitated back contact (IBC) solar cells, is typically limited by their high cost due to complex and expensive processing sequences. Implementation of localized laser-doped contacts is a promising route to reduce fabrication costs while maintaining the high-efficiency potential of such solar cell concepts, also offering the potential to use cheaper, upgraded metallurgical silicon which may otherwise be vulnerable to degradation when exposed to traditional high-temperature processing. In this work, we introduce novel test structures and perform numerical simulations to accurately determine the contact properties, namely, the recombination parameter J(0,c) down to values of 300 fA cm(-2) and contact resistivity rho(c) down to values of 1 x 10-4 Omega cm(2). We analyze the performance of 30 mu m x 30 mu m-sized laser-doped localized contacts prepared using boron and phosphorus spin-on dopants and phosphorus-doped silicon nanoparticle ink. The laser-doped contacts characterized in this work allow for 23.7% efficient IBC solar cells as we demonstrate by numerical.